But intelligence officials have cautioned that they are uncertain whether the electronic break-in at the committee’s computer systems was intended as reasonably routine cyberespionage — of the kind the United States also conducts around the world — or as part of an attempt to manipulate the 2016 presidential election.

The emails were released by WikiLeaks, whose founder, Julian Assange, has made it clear that he hoped to harm Hillary Clinton’s chances of winning the presidency. It is unclear how the documents built their way to the group. But a large sampling was published before the WikiLeaks release by several news organizations and someone who called himself “Guccifer 2.0, ” who investigators now believe was an agent of the G.R.U ., Russia’s military intelligence service.

In an interview with Time publication published Dec. 7, Trump discussed the U.S. intelligence community’s findings about Russia stealing emails from the Democratic National Committee and the Clinton campaign, “says hes” thought U.S. officials’ findings were politically motivated.

The CIA conducted a secret assessment of the U.S. election and concluded that Russia intervened in an effort to help Trump win the presidency, The Washington Post reported Dec. 9. White House spokesman Josh Earnest said there’s “ample evidence” Trump was “obviously aware” Russia was involved in helping him win.

Trump told Fox News in an interview that aired Sunday that he thinks the hacking asserts are “ridiculous.”